Threading-die.



R. L.,WILCOX.

THREADING DIE.

APPLICATION man Aus.23. 1915,

Patente July 10, 1917'.

mmllllm RICHARD LESTER WILCOX, OF WATERBURY BURY FARREL FOUNDRY AND MACHINE A CORORATION 0F CONNECTICUT.

, CONNECTICUT, ASSIGNOR TO THE WATER- CCMPANY, OF WATERBURY, CONNECTICUT,

THREADING-DIE.

Specification of Letters Patent.

Patented July lill, i917.

Application filed August 23, 1915. Serial No. 46,941.

To all whom z' may concern.'

Be it known that I, RICHARD Lnsrnn WIL- coX, a citizen of the United States, residing at lWaterbury, in the county of New Haven and Stat-e of Connecticut, have invented a certain new and Improved Threading-Die, of which the following is a specification, reference being had therein to the accompanying drawings.

My invention relates to new dies for articles.

lt is the object of my invention, among other things, to produce pointed screws with dies, that may be economically constructed, be interchangeable, reversible, and attachable to any one of the many forms of thread rolling machines now in common use.

To these, and other ends, my invention consists in the dies for pointing and threading screws, bolts and similar articles, constructed substantially as hereinafter described and as illustrated in the accompanying drawing', wherein,

Figure l is a plan view of a pair of thread rolling dies constructed in accordance with my invention and occupying the relative p0- sitions assumed by them at the commencement of the thread rolling operation;

Fig. 2 is a` perspective view of one of the dies;

Fig. 3 is a face view thereof with the knife plate removed;

Fig. fl is an end view thereof;

Fig. 5 is a face view of the knife plate;

Fig. 6 is an edge view thereof;

F ig. 7 is an end view thereof; and

Figs. S, 9, l0, ll and l2 are enlarged sectional views of the die and knife plate, taken respectively upon lines A, B, C, D and if; of Fig. 3, with the blank shown in connection therewith.

lleretofore it has been the practice t0 produce a gimlet point screw by pointing the blank in a lathe, shaving machine or similar mechanism, and then forming the thread thereon. lilith my improved method the blanks are pointed and threaded at one and the same operation.

ln the drawings, the numeral l designates the fixed die and 2 the movable die, both being of substantially the same shape, diering only .in their length, the Xed die and improved threading screws, bolts and similar being longer than the movable die, and the former being provided with the guide notch 9. rJhese dies are secured in the usual way in any one of the :many common forms of thread rolling machines. Each die has an angular recess 3 in one side thereof and upon the adjacent faces are the knives 4, which are parallel with the side of the dies and terminate at their inner ends at the edge of the recess 3. The front face of each of the dies is provided with the usual thread rolling grooves 5 which extend from the outer edges of the dies to and upon one side of the knives 4l- (see Fig.

Secured within the recess 3 by a screw 6 is the knife plate 7, having the knives 8 at opposite ends and upon opposite sides thereof. The knife plate 7 is so shaped and designed that its position within the recess 3 may be reversed end for end, if desired.

rl'he dies l and 2 are arranged relatively so that each of the knives 8 upon the knife plate 7 is in the same line as one of the knives fl upon the opposite die, and the ends thereof have substantial contact with each other.

ln practice, the blank, designated herein by the numeral 10, is placed between the dies in the usual manner, its starting position being substantially shown in Fig. 8, and its alinement being determined by the guide notch 9. is the movable die l. advances parallel with the face of the fined die 2, the thread is rolled upon the shank of the blank and the knives 4; and 8 force their edges into the blank until a small portion of the end of the blank, designated herein by the numeral l1, is separated from the blank and drops from between the dies into a receptacle conveniently arranged to receive it and leaving the end of the blank pointed, substantially as shown in Fig. ll..

The successive steps required to produce this result are shown in Figs. 9, l0 and 1l, and the further movement of the movable die advances the blank so that the tapered or gimlet point end is threaded by the grooves 5, which are formed in the outer curved face of the knives Ll, as above described, thus completing the screw.

In the pointing and threading of screws by dies substantially as herein described, only the minimum amount of material is Wasted, and one complete operation, necessary in the old practice of pointing and threading screws, is eliminated.

In minor details my new and improved dies may be varied from that herein shown and I do not therefore limit myself to a die constructed exactly as shown and described except as the scope of the claims requires.

Having described my invention, What I claim as new and desire to secure by Letters Patent, is

l. A die for rolling threads, having a recess in one face thereof; ay knife in the same face adjacent to said. recess; grooves in said face which extend into one side of said knife; and aI knife plate Within said recess and having a knife thereon which forms an extension of the knife on said die.

2. A thread rolling die, having a recess inthe face thereof, knives upon said face adjacent to said recess and shorter than the die, thread rolling grooves in said face adjacent to said recess and extending into one side of each of said knives, in combination with a knife plate Within said recess, having knives thereon that formv an extension to the knives on said die.

3. A thread rolling die, having a recess in the face thereof, knives upon said face adjacent to said recess and shorter than the die, thread rolling grooves in said face adjacent to said recess and extending into one side of each of said knives, in combination With a reversible knife plate Within said recess, having knives thereon that form an extension to the knives on said die.

4. A die for rolling threads, having a knife on one face thereof, grooves in said face which extend into one side of said knife; and a separable knife connected with said die and forming an extension of the knife on said die.

5. A thread rolling die, having a knife upon one face thereof, a portion of which is integral and a portion separable, and grooves in said knife face.

6. A thread rolling die, havinga knife upon one face thereof, a portion of Which is integral, and a fportion sejiarable,` and grooves in said kni e face and one portion of said knife.

7. A thread rolling die, having a recess in the face thereof, knives upon said face adjacent to said recess and shorter than the die, thread rolling grooves in saidface adjacent to said recess and extending into one side of each ofv said knives, in combination with a knife plate Within said recess, having knives thereon that form an extension to the knives on said die; and means for reversibly securing said `knife plate to said die.

8; A die for rolling threads, having a recess in one face thereof; a knife in the same face adjacent to said recess; grooves in said face which extend into one side of said knife; and a knife plate Within said recess and having a knife thereon which forms an extension of the knife on said die, said knife plate being constructed with a knife upon one edge thereof shorter than the length of the edge. Y

92 A die for rolling threads, having a recess inone face thereof; al knife in the same faceadjacent to said recess; grooves in said face which extend into one side of said knife; anda knife plate Within said recess and having a.- knife Jthereon Which forms an extension of the knife on saidA die, said knife plate being constructed with a knife upon each edge thereof shorter than the length of the edge, said knives being substantially parallel with each other but not With the l edges adjacent thereto. y

10. A die for rolling` threads, having a recess in one face thereof; a knife in the same face adjacent to said recess; grooves in said face Which extend into one side of Said knife; and a knife plate Within said recess and having a knife thereon which forms an extension of the knife on said die, said knife plate being constructed with a knife upon one edge thereof shorter than the length of the edge but not parallel therewith.

11. A thread rolling die, having a recess in one face thereof, the side Wall of which is at an angle to the side of the die, a knife in said face adjacent to said recess, grooves in said face vvhich extend into one side of saidy knife, and a plate Within saidv recess, having a knife thereon Which forms an extensionl of the knife upon said die.

12. A die for rolling threads, having a recess in one face thereof; a knife in the same face adjacent to said recess; grooves in said face which extend into one side of said knife; and a' knife plate Within said recess having a knife thereonV which forms an extension of the knife on saiddie, said knife plate being constructed with a. knife upon one edge thereof shorter than the length of the edge and the top face of said plate adjacent to the knife edge, being beveled toward the outer ends thereof.

In testimony whereof I have hereunto aixed my signature.

RICHARD LESTER WILCOX.

Copies 0f this patent may be obtained. for vc cents each, by addressing the Gummissioner of Patents,

Washington, D. G. 

